We're so busy thinking about the particular points that we ourselves most want to make...that we usually fail to clearly grasp and appreciate the points others want to make...and we don't comprehend the motives and concerns that drive them, because we are occupied in comprehending our own motives and drives, and that takes up most of our energy and thought.
I think that covers what I was trying to say to Bill. To effectively oppose someone's argument, you have to fully understand it. Otherwise, you end up attacking it for the wrong reasons.